In February 2023, the Medical Device Coordination Group (MDCG) published a new revision of the Guidance on classification rules for IVD medical devices. The revision of this MDCG document from 2020 includes some minors changes and one addition. In particular, the updated MDCG Guidance has a new Annex (Annex II), which provides a flowchart to help determine whether an IVD is a companion diagnostic (CDx).
Flowchart to help determine whether an IVD is a CDx
As defined in Article 2 (7) of the Regulation on In Vitro Diagnostic Medical Devices, “companion diagnostic means a device which is essential for the safe and effective use of a corresponding medicinal product” used to identify – before or during the treatment – patients who are most likely to benefit or be at increased risk from this medicinal product.
Notably, to be classified as a CDx, the device must have a link to a medicinal product with an International Non-proprietary Name (INN).
According to the newly added flowchart, an IVD is a CDx when the device:
- Is essential for the safe and effective use of a medicinal product with an International Non-proprietary Name (INN).
- Does not monitor whether the concentration of the medicinal product is within the therapeutic window.
- Does not determine the dosage of the medicinal product for patients already eligible to receive that medicinal product.
- Identifies patients that before or during treatment are:
- most likely benefit from the medicinal product, or
- are likely at an increased risk of a serious adverse events such as a result of treatment with the medicinal product.
All Guidance documents are available in our dedicated Library of Documents.